High powered halide lights and the like are well known and widely used for overhead street and roadway lighting because of the high intensity of illumination they provide, and in such usage are conventionally used in light fixtures comprising either a globular transluscent surrounding envelope or a reflector in fixed form. Several varieties of fixed form reflectors for this type of lighting are commercially available and typically involve relatively heavy and rigid, pressed steel reflectors such as the Abolite reflector manufactured and marketed by Abolite Lighting Inc., West Lafayette, Ohio, the configuration of such reflectors being that of a generally cylindrical sleeve portion spaced from and surrounding, with ventilating holes, a screw type socket, below which there is a flared out, generally hemispherical portion, below which is a further downwardly and outwardly extending portion terminating in an almost cylindrical downwardly directed lip. Such a reflector, which is conventionally arranged on posts or the like for street or roadway lighting, tends to reflect the light downwardly in a relatively narrow flood angle, e.g. 20.degree. or 30.degree., which is generally satisfactory for street lighting or the like because the reflectors are typically located 30 or 40 feet or more above the street or highway surface being illuminated.
A further usage for high powered halide and like type lights has evolved more or less recently, and that is for the illumination of growing plants in enclosed building spaces, such as in greenhouses or the like, where it has been found that such type of lighting is quite satisfactory for enhancing the growth rate of plants and other flora. However, in the greenhouse or like environment the most effective usage of such lighting is with the lights only a few feet, e.g. 4 to 6 feet, above the growing plants, and it has been found that, in such environment and arrangement, commercially available reflectors for halide and like lights are not suitable, or at least not nearly as effective as they should be, because the resulting flood beam is so narrow that the lighting throughout the greenhouse or the like is quite uneven and either too intense or insufficient on a localized basis. Moreover, commercially available reflectors for halide and like lights have been found to be unduly heavy and unduly expensive to fabricate for greenhouse or like lighting purposes in that they are principally designed for rough, outdoor usage whereas the greenhouse or like environment does not require comparable rugged construction.